Devices and methods for adjusting lens positions based on encoded light patterns

ABSTRACT

A device includes a first light source device configured to transmit a first light in a first direction and a second light source device configured to transmit a second light in a second direction. The device also includes a first set of one or more lenses configured for directing the first light from the first light source device and the second light from the second light source device toward a first eye of a user. Also disclosed is a method that includes transmitting a first light and a second light through a first set of one or more lenses and directing the first light and the second light toward a first eye of a user. Further disclosed is a method for adjusting a distance between an eye and a lens of the first set of one or more lenses.

RELATED APPLICATION

This application is related to U.S. patent application Ser. No.15/583,952, entitled “Devices and Methods for Adjusting anInterpupillary Distance Based on Encoded Light Patterns” filed May 1,2017, which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

This relates generally to display devices, and more specifically tohead-mounted display devices.

BACKGROUND

Head-mounted display devices (also called herein head-mounted displays)are gaining popularity as means for providing visual information touser. Different users can have different interpupillary distances, andit is important to set up a head-mounted display device for the correctinterpupillary distance of a user, as an incorrect interpupillarydistance can cause visual distortion.

However, determining an accurate interpupillary distance has oftenrequired professional assistance (e.g., a measurement by an optician).In the absence of such professional assistance, users often set updisplay devices for incorrect interpupillary distances, which reducesthe user experience with such devices.

In addition, placing an eye of a user at an appropriate distance from anexit pupil (e.g., a last lens) of a head-mounted display device is alsoimportant. When the eye is located at a position that does notcorrespond to a design eye relief, the field of view is reduced, whichalso reduces the user experience with the head-mounted display device.

SUMMARY

Accordingly, there is a need for an improved method and an improveddevice for adjusting an interpupillary distance, thereby improving theuser experience with display devices. In addition, there is a need foran improved method and an improved device for adjusting an eye relief,thereby improving the user experience with display devices.

The above deficiencies and other problems are reduced or eliminated bythe disclosed devices and methods.

In accordance with some embodiments, a device includes a first lightsource device configured to transmit a first light in a first directionand a second light in a second direction that is distinct from the firstdirection; and a first set of one or more lenses configured fordirecting the first light and the second light from the first lightsource device toward a first eye of a user. The first light is spatiallyoffset from the second light and one or more of the first light and thesecond light provide a cue for adjusting a location of the first set ofone or more lenses.

In accordance with some embodiments, a method includes transmitting afirst light in a first direction and a second light that is distinctfrom the first light in a second direction that is distinct from thefirst direction; and transmitting the first light and the second lightthrough a first set of one or more lenses and directing the first lightand the second light toward a first eye of a user. The first light isspatially offset from the second light and one or more of the firstlight and the second light provide a cue for adjusting a location of thefirst set of one or more lenses.

In accordance with some embodiments, a method includes receiving aportion of a bundle of light that includes a first light and a secondlight that is distinct from the first light and laterally offset fromthe first light; and, in accordance with a determination that thereceived portion of the bundle of light corresponds to the first light,moving the first set of one or more lenses.

In accordance with some embodiments, a device includes a first lightsource device configured to transmit a first light in a first direction;a second light source device configured to transmit a second light in asecond direction; and a first set of one or more lenses configured fordirecting, toward a first eye of a user, the first light from the firstlight source device and the second light from the second light sourcedevice so that the first light intersects with the second light at afirst location. One or more of the first light and the second lightprovide a cue for adjusting a location of the first set of one or morelenses relative to the first eye of the user.

In accordance with some embodiments, a method includes transmitting,from a first light source device, a first light in a first direction andtransmitting, from a second light source device, a second light that isdistinct from the first light in a second direction. The method alsoincludes transmitting the first light and the second light through afirst set of one or more lenses and directing the first light and thesecond light toward a first eye of a user.

In accordance with some embodiments, a method includes receiving aportion of a light beam that includes a first light from a first lightsource device and a second light that is distinct from the first lightfrom a second light source device. The first light and the second lighthave been transmitted through a first set of one or more lenses. Aftertransmitting through the first set of one or more lenses, the firstlight is configured to intersect with the second light. The method alsoincludes, in accordance with a determination that the received portionof the light beam does not include both the first light and the secondlight, adjusting an eye relief.

Thus, the disclosed embodiments provide devices and methods thatfacilitate accurate determination and/or adjustment of interpupillarydistances. In addition, the disclosed embodiments provide devices andmethods that facilitate accurate determination and/or adjustment of eyereliefs.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the various described embodiments,reference should be made to the Description of Embodiments below, inconjunction with the following drawings in which like reference numeralsrefer to corresponding parts throughout the figures.

FIG. 1A is a schematic diagram of a device for determining and/oradjusting an offset of a lens in accordance with some embodiments.

FIG. 1B is a schematic diagram illustrating an example configurationwhere lenses are aligned with eyes.

FIGS. 1C-1E are schematic diagrams illustrating example configurationswhere lenses are not aligned with eyes.

FIGS. 1F-1K are schematic diagrams illustrating example light sourcedevices in accordance with some embodiments.

FIGS. 1L-1M are schematic diagrams illustrating a device for providingoptical cues for adjusting a distance between an optical element and aneye in accordance with some embodiments.

FIG. 1N is a schematic diagram illustrating a device for providingoptical cues for adjusting a distance between an optical element and aneye in accordance with some embodiments.

FIGS. 1O-1P are schematic diagrams illustrating a device for providingoptical cues for adjusting a distance between an optical element and aneye in accordance with some embodiments.

FIG. 1Q is a schematic diagram illustrating a device for providingoptical cues for adjusting a distance between an optical element and aneye in accordance with some embodiments.

FIG. 1R is a perspective view of a device in accordance with someembodiments.

FIG. 2 is a block diagram of a system including a display device inaccordance with some embodiments.

These figures are not drawn to scale unless indicated otherwise.

DETAILED DESCRIPTION

Many viewing optics (e.g., eyeglasses, head-mounted display devices,etc.) require a correct positioning of the viewing optics relative to aposition of an eye. Incorrect positioning of viewing optics can causevisual distortion. However, determining an accurate interpupillarydistance has often required professional assistance (e.g., a measurementby an optician). In the absence of such professional assistance, userscan set up viewing optics for incorrect interpupillary distances. Forexample, users may be asked to adjust lateral positions of lenses untila crosshair appears the sharpest. Certain users may not be able toaccurately determine when the crosshair appears the sharpest.

The disclosed device, including a light source device coupled with oneor more lenses, allows accurate determination and/or adjustment of aninterpupillary distance utilizing a projection of an encoded lightpattern. In addition, the disclosed device allows accurate determinationand/or adjustment of an eye relief utilizing a projection of an encodedlight pattern.

In some embodiments, the light source device and the one or more lensesare included in a head-mounted display device, which is, in turn, usedfor providing virtual reality and/or augmented reality content. In someembodiments, the light source device and the one or more lenses areincluded in a stand-alone diagnostic device for determining aninterpupillary distance.

Reference will now be made to embodiments, examples of which areillustrated in the accompanying drawings. In the following description,numerous specific details are set forth in order to provide anunderstanding of the various described embodiments. However, it will beapparent to one of ordinary skill in the art that the various describedembodiments may be practiced without these specific details. In otherinstances, well-known methods, procedures, components, circuits, andnetworks have not been described in detail so as not to unnecessarilyobscure aspects of the embodiments.

It will also be understood that, although the terms first, second, etc.are, in some instances, used herein to describe various elements, theseelements should not be limited by these terms. These terms are used onlyto distinguish one element from another. For example, a first lens couldbe termed a second lens, and, similarly, a second lens could be termed afirst lens, without departing from the scope of the various describedembodiments. The first lens and the second lens are both lenses, butthey are not the same lens.

The terminology used in the description of the various describedembodiments herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used in thedescription of the various described embodiments and the appendedclaims, the singular forms “a,” “an,” and “the” are intended to includethe plural forms as well, unless the context clearly indicatesotherwise. It will also be understood that the term “and/or” as usedherein refers to and encompasses any and all possible combinations ofone or more of the associated listed items. It will be furtherunderstood that the terms “includes,” “including,” “comprises,” and/or“comprising,” when used in this specification, specify the presence ofstated features, integers, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, steps, operations, elements, components,and/or groups thereof. The term “exemplary” is used herein in the senseof “serving as an example, instance, or illustration” and not in thesense of “representing the best of its kind.”

FIG. 1A is an isometric view of display device 100 in accordance withsome embodiments. In some other embodiments, display device 100 is partof some other electronic display (e.g., head-mounted displays, digitalmicroscope, etc.). In some embodiments, display device 100 includeslight emission device array 110 and one or more lenses (e.g., lens 130).Light emission device array 110 emits image light toward a viewing user.

In some embodiments, light emission device array 110 includes lightemission devices 120 (e.g., pixels) that emit light in the visiblelight. For example, light emission device array 110 includes an array oflight-emitting diodes (LEDs), an array of microLEDs, an array of OLEDs,or some combination thereof.

In some embodiments, light emission device array 110 includes one ormore light sources (e.g., a fluorescent light source or a broadbandlight source, such as a white LED) and an emission intensity array. Theemission intensity array is configured to selectively attenuate lightemitted from the one or more light sources. In some embodiments, theemission intensity array is composed of a plurality of liquid crystalcells or pixels. Each of the liquid crystal cells is, or in someembodiments, groups of liquid crystal cells are, addressable to havespecific levels of attenuation. For example, at a given time, some ofthe liquid crystal cells may be set to no attenuation, while otherliquid crystal cells may be set to maximum attenuation. In this manner,the emission intensity array is able to control what portion of theimage light emitted from the one or more light sources is passed to theone or more lenses (e.g., lens 130). In some embodiments, the one ormore light sources include light emission devices 120, such as an arrayof LEDs, an array of microLEDs, an array of OLEDs, or a combinationthereof.

One or more lenses (e.g., lens 130) receive light from emission devicearray 110, and direct the light to a location of pupil 150. In someembodiments, lens 130 includes one or more diffractive optics. In someembodiments, the one or more lenses include active lens. An active lensis a lens whose lens curvature and/or refractive ability may bedynamically controlled (e.g., via a change in applied voltage). Anactive lens may be a liquid crystal lens, a liquid lens (e.g., usingelectro-wetting), or some other lens whose curvature and/or refractiveability may be dynamically controlled, or some combination thereof.Accordingly, in some embodiments, system 200 (described with respect toFIG. 2) may dynamically adjust the curvature and/or refractive abilityof active lenslets to direct light received from light emission devicearray 110 to pupil 150.

FIG. 1A also illustrates one or more light source devices 122 (e.g.,light source device 122-1 and/or light source device 122-2) are locatedadjacent to light emission device array 110. In some embodiments, one ormore light source devices 122 are integrated with light emission devicearray 110. In some embodiments, one or more light source devices 122 areseparate from light emission device array 110, but one or more lightsource devices 122 are located in proximity to light emission devicearray 110 (e.g., one or more light source devices 122 are located onlight emission device array 110). In some embodiments, light sourcedevice 122 (e.g., light source device 122-1 and/or light source device122-2) is located adjacent to a top or bottom edge of light emissiondevice array 110.

In some embodiments, light source device 122 (e.g., light source device122-1 and/or light source device 122-2) is located adjacent to a centerof atop or bottom edge of light emission device array 110. For example,in FIG. 1A, light source device 122-1 is located adjacent to a center ofatop edge of light emission device array 110, and light source device122-2 is located adjacent to a center of a bottom edge of light emissiondevice array 110. In some embodiments, a light source device (e.g.,light source device 122-1 or light source device 122-2) is locatedwithin at least 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm from a center of a topor bottom edge of light emission device array 110. In some embodiments,the device provides to a user instructions to look toward light sourcedevice 122 (e.g., look up or look down, depending on the location oflight source device 122).

In FIG. 1A, light source device 122-1 emits first light 132 (e.g., a redlight) in a first direction, second light 134 (e.g., a green light) in asecond direction, and third light 136 (e.g., a blue light) in a thirddirection. First light 132, second light 134, and third light 136 arespatially separated. In some cases, only one of first light 132, secondlight 134, and third light 136 enters through pupil 150 of eye 140depending on a position of eye 140 (e.g., a position of pupil 150 of eye140). Thus, the projection of first light 132, second light 134, andthird light 136 can be used to determine whether lens 130 is alignedwith eye 140.

In some embodiments, light emission device array 110 also displaysadditional features for assisting a user with determining whether lens130 is aligned with eye 140. In FIG. 1A, one or more light emissiondevices 120 (e.g., such as pixel 124) of light emission device array 110optionally emit reference light 138. In some embodiments, referencelight 138 corresponds to second light 134 (e.g., reference light 138 hasa same color and/or a same pulsing frequency as second light 134) sothat reference light 138 can serve as a guide for determining whetherlens 130 is aligned with eye 140. In some embodiments, light emissiondevice array 110 optionally displays instructions for guiding users inadjusting the position of lens 130.

FIG. 1B is a schematic diagram illustrating an example configuration(e.g., an example plan view) where lenses are aligned with eyes.

In FIG. 1B, the device includes light source device 122-1 and lightsource device 122-2. In some embodiments, light source device 122-1 iscoupled with light emission device array 110-1 (e.g., a display screen)and light source device 122-2 is coupled with light emission devicearray 110-2 (e.g., a display screen). In some embodiments, light sourcedevice 122-1 is located adjacent to a lateral center of light emissiondevice array 110. In some embodiments, light source device 122-1 islocated adjacent to a lateral center of a top or bottom edge of lightemission device array 110.

Light source device 122-1 emits first light 132-1 (e.g., a red light) ina first direction, second light 134-1 (e.g., a green light) in a seconddirection, and third light 136-1 (e.g., a blue light) in a thirddirection. First light 132-1, second light 134-1, and third light 136-1from light source device 122-1 are transmitted through lens 130-1, whichdirect first light 132-1, second light 134-1, and third light 136-1toward eye 140-1 (e.g., a left eye). For example, first light 132-1,second light 134-1, and third light 136-1 are collimated after passingthrough lens 130-1. In some embodiments, light source device 122-1 islocated at a focal plane of lens 130-1. As shown in FIG. 1B, first light132-1 is spatially separated from second light 134-1 and third light136-1, and second light 134-1 is spatially separated from third light136-1, after passing through lens 130-1. In some embodiments, firstlight 132-1 is parallel to second light 134-1 and third light 136-1after passing through lens 130-1. In some embodiments, first light 132-1is spatially offset from second light 134-1 by at least 1 mm, 2 mm, 3mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. In some embodiments,second light 134-1 is spatially offset from third light 136-1 by atleast 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm.

Similarly, light source device 122-2 emits fourth light 132-2 (e.g., ared light) in a fourth direction, fifth light 134-2 (e.g., a greenlight) in a fifth direction, and sixth light 136-2 (e.g., a blue light)in a sixth direction. Fourth light 132-2, fifth light 134-2, and sixthlight 136-2 from light source device 122-2 are transmitted through lens130-2, which direct fourth light 132-2, fifth light 134-2, and sixthlight 136-2 toward eye 140-2 (e.g., a right eye). For example, fourthlight 132-2, fifth light 134-2, and sixth light 136-2 are collimatedafter passing through lens 130-2. In some embodiments, light sourcedevice 122-2 is located at a focal plane of lens 130-2. As shown in FIG.1B, fourth light 132-2 is spatially separated from fifth light 134-2 andsixth light 136-2, and fifth light 134-2 is spatially separated fromsixth light 136-2, after passing through lens 130-2. In someembodiments, fourth light 132-2 is parallel to fifth light 134-2 andsixth light 136-2 after passing through lens 130-2. In some embodiments,fourth light 132-2 is spatially offset from fifth light 134-2 by atleast 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. Insome embodiments, fifth light 134-2 is spatially offset from sixth light136-2 by at least 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm,or 10 mm.

In FIG. 1B, a lateral position of eye 140-1 is aligned with a lateralposition of lens 130-1 (e.g., a lateral position of an optical center oflens 130-1), and second light 134-1 (e.g., a green light) enters throughpupil 150-1 of eye 140-1. In addition, a lateral position of eye 140-2is aligned with a lateral position of lens 130-2 (e.g., a lateralposition of an optical center of lens 130-2), and fifth light 134-2(e.g., a green light) enters through pupil 150-2 of eye 140-2. FIG. 1Balso shows that first light 132-1 (e.g., a red light) and third light136-1 (e.g., a blue light) do not enter through pupil 150-1 of eye140-1, and fourth light 132-2 (e.g., a red light) and sixth light 136-2(e.g., a blue light) do not enter through pupil 150-2 of eye 140-2.Second light 134-1 (e.g., a green light) received with eye 140-1indicates that a lateral position of lens 130-1 is aligned with alateral position of eye 140-1 and fifth light 134-2 (e.g., a greenlight) received with eye 140-2 indicates that a lateral position of lens130-2 is aligned with a lateral position of eye 140-2. Thus, noadjustment of the lateral position of lens 130-1 or the lateral positionof lens 130-2 is necessary.

FIGS. 1C-1E are schematic diagrams illustrating example configurationswhere lenses are not aligned with eyes.

In FIG. 1C, third light 136-1 (e.g., a blue light) enters through pupil150-1 of eye 140-1. In addition, sixth light 136-2 (e.g., a blue light)enters through pupil 150-2 of eye 140-2. FIG. 1C also shows that firstlight 132-1 (e.g., a red light) and second light 134-1 (e.g., a greenlight) do not enter through pupil 150-1 of eye 140-1, and fourth light132-2 (e.g., a red light) and fifth light 134-2 (e.g., a green light) donot enter through pupil 150-2 of eye 140-2. Third light 136-1 (e.g., ablue light) received with eye 140-1 indicates that a lateral position oflens 130-1 is located on the left side of a lateral position of eye140-1, and sixth light 136-2 (e.g., a blue light) received with eye140-2 indicates that a lateral position of lens 130-2 is located on theright side of a lateral position of eye 140-2.

When lens 130-1 and lens 130-2 are included in a head-mounted displaydevice, this indicates that the head-mounted display device isconfigured for an interpupillary distance shorter than theinterpupillary distance of the user. Thus, the user can adjust thedistance between lens 130-1 and lens 130-2 (e.g., increasing aninterpupillary distance setting for the head-mounted display device)until second light 134-1 (e.g., a green light) is received with eye140-1 and fifth light 134-2 (e.g., a green light) is received with eye140-2, as shown in FIG. 1B.

In FIG. 1D, first light 132-1 (e.g., a red light) enters through pupil150-1 of eye 140-1. In addition, fourth light 132-2 (e.g., a red light)enters through pupil 150-2 of eye 140-2. FIG. 1D also shows that secondlight 134-1 (e.g., a green light) and third light 136-1 (e.g., a bluelight) do not enter through pupil 150-1 of eye 140-1, and fifth light134-2 (e.g., a green light) and sixth light 136-2 (e.g., a blue light)do not enter through pupil 150-2 of eye 140-2. First light 132-1 (e.g.,a red light) received with eye 140-1 indicates that a lateral positionof lens 130-1 is located on the right side of a lateral position of eye140-1, and fourth light 132-2 (e.g., a red light) received with eye140-2 indicates that a lateral position of lens 130-2 is located on theleft side of a lateral position of eye 140-2.

When lens 130-1 and lens 130-2 are included in a head-mounted displaydevice, this indicates that the head-mounted display device isconfigured for an interpupillary distance longer than the interpupillarydistance of the user. Thus, the user can adjust the distance betweenlens 130-1 and lens 130-2 (e.g., decreasing an interpupillary distancesetting for the head-mounted display device) until second light 134-1(e.g., a green light) is received with eye 140-1 and fifth light 134-2(e.g., a green light) is received with eye 140-2, as shown in FIG. 1B.

In FIG. 1E, first light 132-1 (e.g., a red light) enters through pupil150-1 of eye 140-1. In addition, sixth light 132-2 (e.g., a blue light)enters through pupil 150-2 of eye 140-2. FIG. 1E also shows that secondlight 134-1 (e.g., a green light) and third light 136-1 (e.g., a bluelight) do not enter through pupil 150-1 of eye 140-1, and fourth light132-2 (e.g., a red light) and fifth light 134-2 (e.g., a green light) donot enter through pupil 150-2 of eye 140-2. First light 132-1 (e.g., ared light) received with eye 140-1 indicates that a lateral position oflens 130-1 is located on the right side of a lateral position of eye140-1, and sixth light 132-2 (e.g., a blue light) received with eye140-2 indicates that a lateral position of lens 130-2 is located on theright side of a lateral position of eye 140-2.

When lens 130-1 and lens 130-2 are included in a head-mounted displaydevice, this indicates that the head-mounted display device ispositioned off toward a right side of the user. Thus, the user canreposition the head-mounted display device on the user's head (e.g.,push the head-mounted display device toward a left side of the user'shead) until second light 134-1 (e.g., a green light) is received witheye 140-1 and fifth light 134-2 (e.g., a green light) is received witheye 140-2, as shown in FIG. 1B.

Although FIGS. 1B-1E illustrate that the fourth direction corresponds tothe third direction and the sixth direction corresponds to the firstdirection (e.g., for each lens, the red light is projected toward anoutside of the head-mounted display and the blue light is projectedtoward an inside of the head-mounted display), in some embodiments, thefourth direction corresponds to the first direction and the sixthdirection corresponds to the third direction (e.g., for each lens, thered light is projected toward a left side of the head-mounted displayand the blue light is projected toward a right side of the head-mounteddisplay).

Although FIGS. 1B-IE described that first light 132-1, second light134-1, third light 136-1, fourth light 132-2, fifth light 134-2, andsixth light 136-2 have certain colors, additionally or alternatively,first light 132-1, second light 134-1, third light 136-1, fourth light132-2, fifth light 134-2, and sixth light 136-2 have a respectivetime-dependent intensity pattern (e.g., a pulsing frequency, a dutycycle, and/or an interval). For example, first light 132-1 has a firstpulsing frequency (e.g., first light 132-1 pulses at the first pulsingfrequency), second light 134-1 has a second pulsing frequency (e.g.,second light 134-1 pulses at the second pulsing frequency), third light136-1 has a third pulsing frequency (e.g., third light 136-1 pulses atthe third pulsing frequency), fourth light 132-2 has a fourth pulsingfrequency (e.g., fourth light 132-2 pulses at the fourth pulsingfrequency), fifth light 134-2 has a fifth pulsing frequency (e.g., fifthlight 134-2 pulses at the fifth pulsing frequency), and sixth light136-2 has a sixth pulsing frequency (e.g., sixth light 136-2 pulses atthe sixth pulsing frequency). The pulsing frequencies of first light132-1, second light 134-1, third light 136-1, fourth light 132-2, fifthlight 134-2, and sixth light 136-2 can be used to determine whether lens130-1 is aligned with eye 140-1 and lens 130-2 is aligned with eye140-2. In some embodiments, one or more of first light 132-1, secondlight 134-1, third light 136-1, fourth light 132-2, fifth light 134-2,and sixth light 136-2 have a respective time-independent intensitypattern.

In some embodiments, the device illustrated in FIGS. 1B-1E is used todetermine an interpupillary distance (e.g., the interpupillary distanceis determined from the positions of lenses 130-1 and 130-2 when bothlenses 130-1 and 130-2 are aligned with eyes 140-1 and 140-2). Thus, insome embodiments, the device can be used as a device for measuring aninterpupillary distance. In some embodiments, the device is included in,and/or coupled with, another optical device (e.g., a head-mounteddisplay device as shown in FIG. 1R, an optical microscope, binoculars,etc.) to adjust the optical device to match the interpupillary distance.

In addition, although FIGS. 1B-IE illustrate adjusting positions of twolenses (e.g., adjusting an interpupillary distance, which frequentlyinvolves moving both lenses), it is possible to use an analogous methodfor adjusting a position of a single lens of a single lens system (e.g.,a display system configured to operate with a single eye only), orseparately adjusting a position of an individual lens of a multi-lenssystem.

Although FIGS. 1B-IE illustrate the use of six light components (e.g.,first light 132-1, second light 134-1, third light 136-1, fourth light132-2, fifth light 134-2, and sixth light 136-2), in some embodiments,fewer or more light components can be used. For example, in someembodiments, both the first light and the third light have a same color(e.g., red) and the third light has a distinct color (e.g., green). Insuch embodiments, a light source device does not need to emit a light ofa third color (e.g., a blue light). Thus, in some cases, a light of afirst color (e.g., a green light) received with eye 140-1 indicates thata lateral position of lens 130-1 is aligned with a lateral position ofeye 140-1, and a light of a second color (e.g., a red light) receivedwith eye 140-1 indicates that a lateral position of lens 130-1 is notaligned with a lateral position of eye 140-1 without indicating adirection of the misalignment (or in which direction lens 130-1 shouldmove to match the lateral position of eye 140-1). In some embodiments,light source device 122-1 emits light of four or more colors. Thisprovides an additional resolution in adjusting the lateral position oflens 130-1. In some embodiments, light source device 122-1 emits lighthaving a continuous spectrum of colors as described below with FIGS.1H-1I.

FIGS. 1F-1K are schematic diagrams illustrating example light sourcedevices in accordance with some embodiments.

FIG. 1F shows a light source device that includes first light emittingcomponent 142-1, second light emitting component 142-2, and third lightemitting component 142-3. In some embodiments, each light emittingcomponent is an LED, an organic LED (OLED), an array of LED and/or OLED,or a combination thereof.

In some embodiments, the light source device includes more or fewerlight emitting components. First light emitting component 142-1 isconfigured to emit a first light, second light emitting component 142-2is configured to emit a second light, and third light emitting component142-3 is configured to emit a third light. In some embodiments, thefirst light has a first color (e.g., red) and/or a first time-dependentintensity pattern (e.g., a first pulsing frequency, a first duty cycle,and/or a first interval), the second light has a second color (e.g.,green) and/or a second time-dependent intensity pattern (e.g., a secondpulsing frequency, a second duty cycle, and/or a second interval), andthe third light has a third color (e.g., blue) and/or a thirdtime-dependent intensity pattern (e.g., a third pulsing frequency, athird duty cycle, and/or a third interval).

In some embodiments, first light emitting component 142-1, second lightemitting component 142-2, and third light emitting component 142-3 arepositioned on a focal plane of lens 144, as shown in FIG. 1F. Inaddition, first light emitting component 142-1, second light emittingcomponent 142-2, and third light emitting component 142-3 are laterallyoffset from one another.

In some embodiments, lens 144 is rotationally symmetric (e.g., lens 144is a spherical lens). In some embodiments, lens 144 is reflectionallysymmetric (e.g., lens 144 is a cylindrical lens). In some embodiments,lens 144 is a two-dimensional lens (e.g., lens 144 is a spherical lens).In some embodiments, lens 144 is a one-dimensional lens (e.g., lens 144is a cylindrical lens).

FIG. 1F also shows that first light emitting component 142-1 emits lightin multiple directions, and the light from first light emittingcomponent 142-1 is directed to a first direction after passing throughlens 144. Second light emitting component 142-2 emits light in multipledirections, and the light from second light emitting component 142-2 isdirected to a second direction after passing through lens 144. Thirdlight emitting component 142-3 emits light in multiple directions, andthe light from third light emitting component 142-3 is directed to athird direction after passing through lens 144. Thus, the light emittingdevice shown in FIG. 1F is configured to transmit first light 132 in afirst direction, second light 134 in a second direction, and third light136 in a third direction.

FIG. 1G shows a light source device that includes first light emittingcomponent 142-1, second light emitting component 142-2, and third lightemitting component 142-3. First light emitting component 142-1, secondlight emitting component 142-2, and third light emitting component 142-3are described above with respect to FIG. 1F.

The light source device includes barrier 146 with an opening. In someembodiments, the opening is a pinhole. In some embodiments, the openingis a slit. The opening of barrier 146 transmits light having aparticular direction from each light emitting component. For example,light from light emitting component 142-1 that is not directed to theopening is blocked by barrier 146. Thus, the light emitting device shownin FIG. 1G is configured to transmit first light 132 in a firstdirection, second light 134 in a second direction, and third light 136in a third direction.

FIG. 1H shows a light source device that includes optical grating 148.In FIG. 1H, optical grating 148 receives a light that includes multiplecolor components (e.g., the light includes two or more of a red lightcomponent, a green light component or a blue light component). In someembodiments, the light source device receives a white light. Opticalgrating 148 disperses the light components based on their respectivewavelengths. For example, as shown in FIG. 1H, optical grating 148disperses first light 132 into a first direction, second light 134 intoa second direction, and third light 136 into a third direction. In someembodiments, the light source device also includes a light sourceconfigured to provides the light with multiple color components (e.g., abroadband light source, such as an incandescent bulb, and asuperluminescent light emitting diode, or a combination of multiplecolored light emitting components shown in FIG. 1F).

FIG. 1I is similar to FIG. 1H, except that set 152 of dichroic mirrorsis used. In some embodiments, set 152 of dichroic mirrors include asingle multi-faceted component, where each dichroic mirror is located ona respective facet. Each dichroic mirror is configured to reflect alight having a particular wavelength (or a range of wavelengths). Thus,the light emitting device shown in FIG. 1G is configured to direct firstlight 132 in a first direction, second light 134 in a second direction,and third light 136 in a third direction.

FIG. 1J shows a light source device that includes light guide 126-1(e.g., an optical fiber) coupled with light emitting component 142(e.g., a light emitting diode). Light from light emitting component 142travels through light guide 126-1. As shown in FIG. 1J, light guide126-1 has extraction feature 128. In some embodiments, extractionfeature 128 is an indentation prism. A portion of light travelingthrough light guide 126-1 is leaked, or emitted, from light guide 126-1through extraction feature 128. Based on the shape of extraction feature128, the emitted light is directed to a particular direction (e.g., byadjusting the angle of the indentation prism, the emitted light can bedirected to a particular direction). In some embodiments, light guide126-1 is made of a material that is transparent to visible light. Thus,when light guide 126-1 is placed over light emission device array 110,the presence of light guide 126-1 is typically not perceived by a user(e.g., light guide 126-1 is not visible to the user). In addition,extraction feature 128 is configured so that extraction feature 128 doesnot visibly interfere with light emitted by light emission device array110. For example, extraction feature 128 is sized and/or positioned in away such that extraction feature 128 does not interfere with lightemitted by light emission device array 110 (e.g., extraction feature 128is positioned over a dark region between pixels). The light sourcedevice shown in FIG. 1J can be placed over light emission device array110 without requiring a precise alignment between the light sourcedevice and light emission device array 110. Thus, this can facilitatemanufacturing of an optical device (e.g., a head-mounted displaydevice).

FIG. 1K is similar to FIG. 1J, except that FIG. 1K shows that lightguide 126-2 can have multiple extraction features 128. Thus, the lightsource device shown in FIG. 1K can emit light in multiple locations thatcorrespond to extraction features.

In some embodiments, multiple light source devices are used (e.g., afirst light source device coupled with a first light emitting componentfor a first color and a second light source device coupled with a secondlight emitting component for a second color). For brevity, such detailsare omitted herein.

The light source devices shown in FIGS. 1F-1K can be used as describedabove with respect to FIGS. 1A-1E for determining and/or adjusting analignment of one or more lenses.

FIGS. 1L-1M are schematic diagrams illustrating a device for providingoptical cues for adjusting a distance between an optical element (e.g.,lens 130) and eye 140 in accordance with some embodiments.

FIG. 1L illustrates that light source device 122-1 emits light 134(e.g., a green light) and light source device 122-2 emits light 154(e.g., a red light). Light 134 and light 154, after lens 130 steerslight 134 and light 154, intersect with each other. The location wherelight 134 intersects with light 154 corresponds to a preselected eyerelief (e.g., a design eye relief that corresponds to a position of aneye, for which device 100 is designed).

FIG. 1L also illustrates eye positioning devices 184 (e.g., an eyecup, agoggle frame, a cushion coupled with a goggle frame, etc.). In someembodiments, eye positioning device 184 is configured to provide amechanical support on a region around an eye of a user (e.g., a portionof a supraorbital region and a portion of a infraorbital region, such asan eyebrow region and a cheek region). Eye positioning device 184 isconfigured to move so that a distance between eye positioning device 184and lens 130 can be adjusted. For example, eye positioning device 184 ismounted on rail 182. In some embodiments, eye positioning device 184 ismounted on a thread (e.g., a rotating eyecup). Thus, by moving aposition of eye positioning device 184, a distance between an eyelocated adjacent to positioning device 184 and lens 130 can be changed(this is sometimes referred to as an adjustment of an eye relief).

In some embodiments, eye positioning device 184 is coupled with amechanical lock that prevents movement of eye positioning device 184relative to lens 130 when the mechanical lock is engaged. In someembodiments, eye positioning device 184 is configured to require a forceabove a certain threshold (e.g., based on mechanical friction) in aparticular direction for changing a distance between eye positioningdevice 184 and lens 130 (e.g., a rotating eyecup).

In FIG. 1L, light 134 and light 154 do not enter through pupil 150 of auser. Thus, the user can determine that eye 140 is not located at thepreselected eye relief (e.g., a distance between lens 130 and eye 140does not correspond to a preselected distance between lens 130 and eye140) based on absence of light 134 and light 154 received through pupil150.

FIG. 1M illustrates that the position of eye positioning device 184 haschanged (e.g., the user has turned a rotating eyecup or slid eyepositioning device 184 along rail 182). In FIG. 1M, both light 134 andlight 154 enter through pupil 150 of eye 140. Thus, the user candetermine that eye 140 is located at the preselected eye relief (e.g.,the distance between lens 130 and eye 140 corresponds to the preselecteddistance between lens 130 and eye 140) based on receiving both light 134and light 154 through pupil 150.

Insets shown in FIG. 1M illustrate the direction of light 134 and light154. The inset showing a side view illustrates that light 134 from lightsource device 122-1 and light 154 from light source device 122-2 aresteered by lens 130 so that light 134 intersects with light 154. Theinset showing a front view illustrates that light 134 approaches eye 140from a location above an optical axis of device 100 toward the opticalaxis of device 100, and light 154 approaches eye 140 from a locationbelow the optical axis of device 100 toward the optical axis of device100.

FIG. 1N is similar to FIG. 1M, except that in FIG. 1N, light sourcedevice 122-3 is used instead of light source device 122-2 shown in FIG.1M. Light 156 from light source device 122-3 intersects with light 134,after light 156 and light 134 pass through lens 130, to provide a cueindicating a position corresponding to a preselected eye relief.

Insets shown in FIG. 1N illustrate that light 134 propagates on a firstplane (e.g., a vertical plane) and light 156 propagates on a secondplane (e.g., a horizontal plane) that is not parallel to the firstplane. In some embodiments, the second plane is perpendicular to thefirst plane as shown in the inset showing a front view.

FIGS. 1O-1P are schematic diagrams illustrating a device for providingoptical cues for adjusting a distance between an optical element (e.g.,lens 130) and eye 140 in accordance with some embodiments.

FIG. 1O is similar to FIG. 1M, except that light source device 122-1emits light 134, 158, and 162 (e.g., sequentially or concurrently) andlight source device 122-2 emits light 154, 160, and 164 (e.g.,sequentially or concurrently). In some embodiments, light source device122-1 emits light 134 concurrently with emission of light 154 by lightsource device 122-2. In some embodiments, light source device 122-1emits light 158 concurrently with emission of light 160 by light sourcedevice 122-2. In some embodiments, light source device 122-1 emits light162 concurrently with emission of light 164 by light source device122-2.

Similar to FIG. 1M, light 134 in FIG. 1O intersects with light 154 at aposition that corresponds to a preselected eye relief. Light 162intersects with light 164 at a position that does not correspond to thepreselected eye relief. Light 158 intersects with light 160 at aposition that does not correspond to the preselected eye relief.

Thus, as shown in FIG. 1P, when light 158 and light 160 both enterthrough the pupil of eye 140, the user can determine that eye 140 is notlocated at the preselected eye relief (e.g., a distance between lens 130and eye 140 does not correspond to a preselected distance between lens130 and eye 140) based on receiving both light 158 and light 160received through the pupil of eye 140. In some embodiments, the colorand/or the time-dependent intensity pattern of light 158 and light 160indicate that a distance between lens 130 and eye 140 is greater thanthe preselected eye relief, which facilitates adjustment and/orcorrection of the distance between lens 130 and eye 140. By indicatingthe direction of the required adjustment, the time required foradjusting the eye relief can be reduced.

FIG. 1Q is a schematic diagram illustrating a device for providingoptical cues for adjusting a distance between an optical element (e.g.,lens 130) and eye 140 in accordance with some embodiments.

FIG. 1Q is similar to FIG. 1N, except that light source device 122-1emits light 158 and light source device 122-3 emits light 168. Light 158intersects with light 168 at a position, which provides a cue indicatingthat the position where light 158 intersects with light 168 does notcorrespond to the preselected eye relief.

FIG. 1R illustrates display device 190 in accordance with someembodiments. In some embodiments, display device 190 is configured to beworn on a head of a user (e.g., by having the form of spectacles oreyeglasses, as shown in FIG. 1R) or to be included as part of a helmetthat is to be worn by the user. When display device 190 is configured tobe worn on a head of a user or to be included as part of a helmet,display device 190 is called a head-mounted display. Alternatively,display device 190 is configured for placement in proximity of an eye oreyes of the user at a fixed location, without being head-mounted (e.g.,display device 190 is mounted in a vehicle, such as a car or anairplane, for placement in front of an eye or eyes of the user).

In some embodiments, display device 190 includes one or more componentsdescribed below with respect to FIG. 2. In some embodiments, displaydevice 190 includes additional components not shown in FIG. 2.

FIG. 2 is a block diagram of system 200 in accordance with someembodiments. The system 200 shown in FIG. 2 includes display device 205(which corresponds to display device 190 shown in FIG. 1R), imagingdevice 235, and input interface 240 that are each coupled to console210. While FIG. 2 shows an example of system 200 including one displaydevice 205, imaging device 235, and input interface 240, in otherembodiments, any number of these components may be included in system200. For example, there may be multiple display devices 205 each havingassociated input interface 240 and being monitored by one or moreimaging devices 235, with each display device 205, input interface 240,and imaging devices 235 communicating with console 210. In alternativeconfigurations, different and/or additional components may be includedin system 200. For example, in some embodiments, console 210 isconnected via a network (e.g., the Internet) to system 200 or isself-contained as part of display device 205 (e.g., physically locatedinside display device 205). In some embodiments, display device 205 isused to create mixed reality by adding in a view of the realsurroundings. Thus, display device 205 and system 200 described here candeliver virtual reality, mixed reality, and augmented reality.

In some embodiments, as shown in FIG. 1R, display device 205 is ahead-mounted display that presents media to a user. Examples of mediapresented by display device 205 include one or more images, video,audio, or some combination thereof. In some embodiments, audio ispresented via an external device (e.g., speakers and/or headphones) thatreceives audio information from display device 205, console 210, orboth, and presents audio data based on the audio information. In someembodiments, display device 205 immerses a user in a virtualenvironment.

In some embodiments, display device 205 also acts as an augmentedreality (AR) headset. In these embodiments, display device 205 augmentsviews of a physical, real-world environment with computer-generatedelements (e.g., images, video, sound, etc.). Moreover, in someembodiments, display device 205 is able to cycle between different typesof operation. Thus, display device 205 operate as a virtual reality (VR)device, an AR device, as glasses or some combination thereof (e.g.,glasses with no optical correction, glasses optically corrected for theuser, sunglasses, or some combination thereof) based on instructionsfrom application engine 255.

Display device 205 includes electronic display 215, one or moreprocessors 216, eye tracking module 217, adjustment module 218, one ormore locators 220, one or more position sensors 225, one or moreposition cameras 222, memory 228, inertial measurement unit (IMU) 230,or a subset or superset thereof (e.g., display device 205 withelectronic display 215, one or more processors 216, and memory 228,without any other listed components). Some embodiments of display device205 have different modules than those described here. Similarly, thefunctions can be distributed among the modules in a different mannerthan is described here.

One or more processors 216 (e.g., processing units or cores) executeinstructions stored in memory 228. Memory 228 includes high-speed randomaccess memory, such as DRAM, SRAM, DDR RAM or other random access solidstate memory devices; and may include non-volatile memory, such as oneor more magnetic disk storage devices, optical disk storage devices,flash memory devices, or other non-volatile solid state storage devices.Memory 228, or alternately the non-volatile memory device(s) withinmemory 228, includes a non-transitory computer readable storage medium.In some embodiments, memory 228 or the computer readable storage mediumof memory 228 stores programs, modules and data structures, and/orinstructions for displaying one or more images on electronic display215.

Electronic display 215 displays images to the user in accordance withdata received from console 210 and/or processor(s) 216. In variousembodiments, electronic display 215 may comprise a single adjustableelectronic display element or multiple adjustable electronic displayselements (e.g., a display for each eye of a user).

In some embodiments, the display element includes one or more lightemission devices and a corresponding array of emission intensity array.An emission intensity array is an array of electro-optic pixels,opto-electronic pixels, some other array of devices that dynamicallyadjust the amount of light transmitted by each device, or somecombination thereof. These pixels are placed behind one or more lenses.In some embodiments, the emission intensity array is an array of liquidcrystal based pixels in an LCD (a Liquid Crystal Display). Examples ofthe light emission devices include: an organic light emitting diode, anactive-matrix organic light-emitting diode, a light emitting diode, sometype of device capable of being placed in a flexible display, or somecombination thereof. The light emission devices include devices that arecapable of generating visible light (e.g., red, green, blue, etc.) usedfor image generation. The emission intensity array is configured toselectively attenuate individual light emission devices, groups of lightemission devices, or some combination thereof. Alternatively, when thelight emission devices are configured to selectively attenuateindividual emission devices and/or groups of light emission devices, thedisplay element includes an array of such light emission devices withouta separate emission intensity array.

One or more lenses direct light from the arrays of light emissiondevices (optionally through the emission intensity arrays) to locationswithin each eyebox and ultimately to the back of the user's retina(s).An eyebox is a region that is occupied by an eye of a user locatedproximity to display device 205 (e.g., a user wearing display device205) for viewing images from display device 205. In some cases, theeyebox is represented as a 10 mm×10 mm square. In some embodiments, theone or more lenses include one or more coatings, such as anti-reflectivecoatings.

In some embodiments, the display element includes an infrared (IR)detector array that detects IR light that is retro-reflected from theretinas of a viewing user, from the surface of the corneas, lenses ofthe eyes, or some combination thereof. The IR detector array includes anIR sensor or a plurality of IR sensors that each correspond to adifferent position of a pupil of the viewing user's eye. In alternateembodiments, other eye tracking systems may also be employed.

Eye tracking module 217 determines locations of each pupil of a user'seyes. In some embodiments, eye tracking module 217 instructs electronicdisplay 215 to illuminate the eyebox with IR light (e.g., via IRemission devices in the display element).

A portion of the emitted IR light will pass through the viewing user'spupil and be retro-reflected from the retina toward the IR detectorarray, which is used for determining the location of the pupil.Alternatively, the reflection off of the surfaces of the eye is used toalso determine location of the pupil. The IR detector array scans forretro-reflection and identifies which IR emission devices are activewhen retro-reflection is detected. Eye tracking module 217 may use atracking lookup table and the identified IR emission devices todetermine the pupil locations for each eye. The tracking lookup tablemaps received signals on the IR detector array to locations(corresponding to pupil locations) in each eyebox. In some embodiments,the tracking lookup table is generated via a calibration procedure(e.g., user looks at various known reference points in an image and eyetracking module 217 maps the locations of the user's pupil while lookingat the reference points to corresponding signals received on the IRtracking array). As mentioned above, in some embodiments, system 200 mayuse other eye tracking systems than the embedded IR one described above.

Adjustment module 218 generates an image frame based on the determinedlocations of the pupils. In some embodiments, this sends a discreteimage to the display that will tile subimages together thus a coherentstitched image will appear on the back of the retina. Adjustment module218 adjusts an output (i.e. the generated image frame) of electronicdisplay 215 based on the detected locations of the pupils. Adjustmentmodule 218 instructs portions of electronic display 215 to pass imagelight to the determined locations of the pupils. In some embodiments,adjustment module 218 also instructs the electronic display to not passimage light to positions other than the determined locations of thepupils. Adjustment module 218 may, for example, block and/or stop lightemission devices whose image light falls outside of the determined pupillocations, allow other light emission devices to emit image light thatfalls within the determined pupil locations, translate and/or rotate oneor more display elements, dynamically adjust curvature and/or refractivepower of one or more active lenses in the lens (e.g., microlens) arrays,or some combination thereof.

Optional locators 220 are objects located in specific positions ondisplay device 205 relative to one another and relative to a specificreference point on display device 205. A locator 220 may be a lightemitting diode (LED), a corner cube reflector, a reflective marker, atype of light source that contrasts with an environment in which displaydevice 205 operates, or some combination thereof. In embodiments wherelocators 220 are active (i.e., an LED or other type of light emittingdevice), locators 220 may emit light in the visible band (e.g., about400 nm to 750 nm), in the infrared band (e.g., about 750 nm to 1 mm), inthe ultraviolet band (about 100 nm to 400 nm), some other portion of theelectromagnetic spectrum, or some combination thereof.

In some embodiments, locators 220 are located beneath an outer surfaceof display device 205, which is transparent to the wavelengths of lightemitted or reflected by locators 220 or is thin enough to notsubstantially attenuate the wavelengths of light emitted or reflected bylocators 220. Additionally, in some embodiments, the outer surface orother portions of display device 205 are opaque in the visible band ofwavelengths of light. Thus, locators 220 may emit light in the IR bandunder an outer surface that is transparent in the IR band but opaque inthe visible band.

IMU 230 is an electronic device that generates calibration data based onmeasurement signals received from one or more position sensors 225.Position sensor 225 generates one or more measurement signals inresponse to motion of display device 205. Examples of position sensors225 include: one or more accelerometers, one or more gyroscopes, one ormore magnetometers, another suitable type of sensor that detects motion,a type of sensor used for error correction of IMU 230, or somecombination thereof. Position sensors 225 may be located external to IMU230, internal to IMU 230, or some combination thereof.

Based on the one or more measurement signals from one or more positionsensors 225, IMU 230 generates first calibration data indicating anestimated position of display device 205 relative to an initial positionof display device 205. For example, position sensors 225 includemultiple accelerometers to measure translational motion (forward/back,up/down, left/right) and multiple gyroscopes to measure rotationalmotion (e.g., pitch, yaw, roll). In some embodiments, IMU 230 rapidlysamples the measurement signals and calculates the estimated position ofdisplay device 205 from the sampled data. For example, IMU 230integrates the measurement signals received from the accelerometers overtime to estimate a velocity vector and integrates the velocity vectorover time to determine an estimated position of a reference point ondisplay device 205. Alternatively, IMU 230 provides the sampledmeasurement signals to console 210, which determines the firstcalibration data. The reference point is a point that may be used todescribe the position of display device 205. While the reference pointmay generally be defined as a point in space; however, in practice thereference point is defined as a point within display device 205 (e.g., acenter of IMU 230).

In some embodiments, IMU 230 receives one or more calibration parametersfrom console 210. As further discussed below, the one or morecalibration parameters are used to maintain tracking of display device205. Based on a received calibration parameter, IMU 230 may adjust oneor more IMU parameters (e.g., sample rate). In some embodiments, certaincalibration parameters cause IMU 230 to update an initial position ofthe reference point so it corresponds to a next calibrated position ofthe reference point. Updating the initial position of the referencepoint as the next calibrated position of the reference point helpsreduce accumulated error associated with the determined estimatedposition. The accumulated error, also referred to as drift error, causesthe estimated position of the reference point to “drift” away from theactual position of the reference point over time.

Imaging device 235 generates calibration data in accordance withcalibration parameters received from console 210. Calibration dataincludes one or more images showing observed positions of locators 220that are detectable by imaging device 235. In some embodiments, imagingdevice 235 includes one or more still cameras, one or more videocameras, any other device capable of capturing images including one ormore locators 220, or some combination thereof. Additionally, imagingdevice 235 may include one or more filters (e.g., used to increasesignal to noise ratio). Imaging device 235 is configured to optionallydetect light emitted or reflected from locators 220 in a field of viewof imaging device 235. In embodiments where locators 220 include passiveelements (e.g., a retroreflector), imaging device 235 may include alight source that illuminates some or all of locators 220, whichretro-reflect the light towards the light source in imaging device 235.Second calibration data is communicated from imaging device 235 toconsole 210, and imaging device 235 receives one or more calibrationparameters from console 210 to adjust one or more imaging parameters(e.g., focal length, focus, frame rate, ISO, sensor temperature, shutterspeed, aperture, etc.).

Input interface 240 is a device that allows a user to send actionrequests to console 210. An action request is a request to perform aparticular action. For example, an action request may be to start or endan application or to perform a particular action within the application.Input interface 240 may include one or more input devices. Example inputdevices include: a keyboard, a mouse, a game controller, data from brainsignals, data from other parts of the human body, or any other suitabledevice for receiving action requests and communicating the receivedaction requests to console 210. An action request received by inputinterface 240 is communicated to console 210, which performs an actioncorresponding to the action request. In some embodiments, inputinterface 240 may provide haptic feedback to the user in accordance withinstructions received from console 210. For example, haptic feedback isprovided when an action request is received, or console 210 communicatesinstructions to input interface 240 causing input interface 240 togenerate haptic feedback when console 210 performs an action.

Console 210 provides media to display device 205 for presentation to theuser in accordance with information received from one or more of:imaging device 235, display device 205, and input interface 240. In theexample shown in FIG. 2, console 210 includes application store 245,tracking module 250, and application engine 255. Some embodiments ofconsole 210 have different modules than those described in conjunctionwith FIG. 2. Similarly, the functions further described below may bedistributed among components of console 210 in a different manner thanis described here.

When application store 245 is included in console 210, application store245 stores one or more applications for execution by console 210. Anapplication is a group of instructions, that when executed by aprocessor, is used for generating content for presentation to the user.Content generated by the processor based on an application may be inresponse to inputs received from the user via movement of display device205 or input interface 240. Examples of applications include: gamingapplications, conferencing applications, video playback application, orother suitable applications.

When tracking module 250 is included in console 210, tracking module 250calibrates system 200 using one or more calibration parameters and mayadjust one or more calibration parameters to reduce error indetermination of the position of display device 205. For example,tracking module 250 adjusts the focus of imaging device 235 to obtain amore accurate position for observed locators on display device 205.Moreover, calibration performed by tracking module 250 also accounts forinformation received from IMU 230. Additionally, if tracking of displaydevice 205 is lost (e.g., imaging device 235 loses line of sight of atleast a threshold number of locators 220), tracking module 250re-calibrates some or all of system 200.

In some embodiments, tracking module 250 tracks movements of displaydevice 205 using second calibration data from imaging device 235. Forexample, tracking module 250 determines positions of a reference pointof display device 205 using observed locators from the secondcalibration data and a model of display device 205. In some embodiments,tracking module 250 also determines positions of a reference point ofdisplay device 205 using position information from the first calibrationdata. Additionally, in some embodiments, tracking module 250 may useportions of the first calibration data, the second calibration data, orsome combination thereof, to predict a future location of display device205. Tracking module 250 provides the estimated or predicted futureposition of display device 205 to application engine 255.

Application engine 255 executes applications within system 200 andreceives position information, acceleration information, velocityinformation, predicted future positions, or some combination thereof ofdisplay device 205 from tracking module 250. Based on the receivedinformation, application engine 255 determines content to provide todisplay device 205 for presentation to the user. For example, if thereceived information indicates that the user has looked to the left,application engine 255 generates content for display device 205 thatmirrors the user's movement in a virtual environment. Additionally,application engine 255 performs an action within an applicationexecuting on console 210 in response to an action request received frominput interface 240 and provides feedback to the user that the actionwas performed. The provided feedback may be visual or audible feedbackvia display device 205 or haptic feedback via input interface 240.

In light of these principles, we now turn to certain embodiments.

In accordance with some embodiments, a device includes a first lightsource device (e.g., light source device 122-1 in FIG. 1B) configured totransmit a first light (e.g., first light 132-1) in a first directionand a second light (e.g., second light 132-2) in a second direction thatis distinct from the first direction. The device also includes a firstset of one or more lenses (e.g., lens 130-1 in FIG. 1B) configured fordirecting the first light and the second light from the first lightsource device toward a first eye of a user. The first light is spatiallyoffset from the second light (e.g., first light 132-1 is spatiallyoffset from second light 134-1 as shown in FIG. 1B). One or more of thefirst light and the second light provide a cue for adjusting a location(e.g., a lateral location) of the first set of one or more lenses.

In some embodiments, the first light indicates that an eye receiving thefirst light is offset from a center of the first set of one or morelenses (e.g., as shown in FIG. 1D, when eye 140-1 receives first light132-1, this indicates that eye 140-1 is offset from a lateral positionof a center of lens 130-1). The second light indicates that an eyereceiving the second light is aligned with the center of the first setof one or more lenses (e.g., as shown in FIG. 1B, when eye 140-1receives second light 134-1, this indicates that eye 140-1 is alignedwith the lateral position of the center of lens 130-1).

In some embodiments, the first light directed to the first eye isparallel to the second light directed to the first eye (e.g., in FIG.1B, first light 132-1 is parallel to second light 134-1 after passingthrough lens 130-1).

In some embodiments, the first light source device is further configuredto transmit a third light in a third direction that is distinct from thefirst direction and the second direction; and the first set of one ormore lenses is further configured for directing the third light towardthe first eye (e.g., in FIG. 1B, third light 136-1). The third light isspatially offset from the first light and the second light.

In some embodiments, the first light has a first color (e.g., red), andthe second light has a second color (e.g., green) that is distinct fromthe first color. The first light source device includes a light emittingcomponent configured to provide a broadband light that includes thefirst light of the first color and the second light of the second color;and an optical grating (e.g., optical grating 148 in FIG. 1H) configuredto disperse the broadband light from the light emitting component,including directing the first light of the first color in the firstdirection and the second light of the second color in the seconddirection.

In some embodiments, the first light has a first color (e.g., red), andthe second light has a second color (e.g., green) that is distinct fromthe first color. the first light source device includes a light emittingcomponent configured to provide a broadband light that includes thefirst light of the first color and the second light of the second color;and a plurality of dichroic mirrors (e.g., set 152 of dichroic mirrorsin FIG. 1I), including a first dichroic mirror and a second dichroicmirror. The first dichroic mirror is configured to reflect the firstlight of the first color in the first direction and the second dichroicmirror is configured to reflect the second light of the second color inthe second direction.

In some embodiments, the first light source device includes a firstlight emitting component (e.g., first light emitting component 142-1 inFIG. 1F) configured to provide the first light and a second lightemitting component (e.g., second light emitting component 142-2 in FIG.1F) configured to provide the second light.

In some embodiments, the first light has a first color (e.g., red), andthe second light has a second color (e.g., green) that is distinct fromthe first color.

In some embodiments, the first light has a first time-dependentintensity pattern (e.g., a first pulsing frequency, a first duty cycle,a first interval, etc.) and the second light has a second time-dependentintensity pattern (e.g., a second pulsing frequency, a second dutycycle, a second interval, etc.). In some embodiments, the secondtime-dependent intensity pattern is distinct from the firsttime-dependent intensity pattern.

In some embodiments, the first light emitting component is configured toprovide the first light in multiple directions, and the second lightemitting component is configured to provide the second light in multipledirections (e.g., FIG. 1F). The first light source device also includesone or more lenses (e.g., lens 144 in FIG. 1F). The first light emittingcomponent and the second light emitting component are positioned (e.g.,on a focal plane of the one or more lenses) with a lateral offset sothat the first light provided by the first light emitting component isdirected to the first direction and the second light provided by thesecond light emitting component is directed to the second direction.

In some embodiments, the first light source device also includes abarrier having an opening (e.g., barrier 146 with a pinhole or a slit,as shown in FIG. 1G) configured to transmit the first light from thefirst light emitting component in the first direction and the secondlight from the second light emitting component in the second direction.In some embodiments, the first light emitting component is configured toprovide the first light in multiple directions, and the second lightemitting component is configured to provide the second light in multipledirections.

In some embodiments, the device includes a second light source device(e.g., second light source device 122-1 in FIG. 1B) configured totransmit a fourth light (e.g., fourth light 132-2 in FIG. 1B) in afourth direction and a fifth light (e.g., fifth light 134-2 in FIG. 1B)distinct from the fourth light in a fifth direction that is distinctfrom the fourth direction. The second light source device is distinctfrom the first light source device. The device also includes a secondset of one or more lenses (e.g., lens 130-2 in FIG. 1B) configured fordirecting the fourth light and the fifth light from the second lightsource device toward a second eye of the user. The fourth light isspatially offset from the fifth light. One or more of the fourth lightand the fifth light provide a cue for adjusting a location (e.g., alateral location) of the second set of one or more lenses.

In some embodiments, the second light source device is furtherconfigured to transmit a sixth light (e.g., sixth light 136-2 in FIG.1B) in a sixth direction that is distinct from the fourth direction andthe fifth direction. The second set of one or more lenses is furtherconfigured for directing the sixth light toward the second eye. Thesixth light is spatially offset from the fourth light and the fifthlight.

In some embodiments, the device also includes one or more displayscreens (e.g., display screens 110-1 and/or 110-2) configured to projectone or more images through the first set of one or more lenses.

In some embodiments, the device is a head-mounted display device (e.g.,FIG. 1R).

In accordance with some embodiments, a method includes transmitting afirst light (e.g., first light 132-1 in FIG. 1B) in a first directionand a second light (e.g., second light 134-1 in FIG. 1B) that isdistinct from the first light in a second direction that is distinctfrom the first direction; and transmitting the first light and thesecond light through a first set of one or more lenses and directing thefirst light and the second light toward a first eye of a user (e.g.,FIG. 1B). The first light is spatially offset from the second light andone or more of the first light and the second light provide a cue foradjusting a location of the first set of one or more lenses.

In some embodiments, the method also includes, in conjunction withtransmitting the first light and the second light through the first setof one or more lenses (e.g., concurrently with transmitting the firstlight and the second light through the first set of one or more lenses),transmitting a third light that is distinct and spatially offset fromthe first light and the second light.

In some embodiments, the method also includes transmitting a fourthlight (e.g., fourth light 132-2 in FIG. 1B) in a fourth direction and afifth light (e.g., fifth light 134-2 in FIG. 1B) that is distinct formthe fourth light in a fifth direction that is distinct from the fourthdirection; and transmitting the fourth light and the fifth light througha second set of one or more lenses that is distinct from the first setof one or more lenses and directing the fourth light and the fifth lighttoward a second eye of the user. The fourth light is spatially offsetfrom the fifth light and one or more of the fourth light and the fifthlight provide a cue for adjusting a location of the second set of one ormore lenses.

In some embodiments, the method also includes, in conjunction withtransmitting the first light and the second light through the first setof one or more lenses, transmitting a reference light from one or moredisplay screens through the first set of one or more lenses (e.g.,reference light 138). In some embodiments, the reference light has acolor and/or a time-dependent intensity pattern of the second light.Thus, the reference light can assist with a determination whether thesecond light is received by an eye. For example, a color of thereference light and a color of light from a light source device arecompared to determine whether the color of the light from the lightsource device matches the color of the reference light. If the color ofthe light from the light source device matches the color of thereference light, the lens is aligned with the eye. If the color of thelight from the light source device does not match the color of thereference light, the lens is not aligned with the eye. In anotherexample, a pulsing frequency of the reference light and a pulsingfrequency of light from a light source device are compared to determinewhether the pulsing frequency of the light from the light source devicematches the pulsing frequency of the reference light. If the pulsingfrequency of the light from the light source device matches the pulsingfrequency of the reference light, the lens is aligned with the eye. Ifthe pulsing frequency of the light from the light source device does notmatch the pulsing frequency of the reference light, the lens is notaligned with the eye.

In accordance with some embodiments, a method includes receiving aportion of a bundle of light that includes a first light and a secondlight that is distinct from the first light and laterally offset fromthe first light (e.g., FIG. 1B). The method also includes, in accordancewith a determination that the received portion of the bundle of lightcorresponds to the first light, moving the first set of one or morelenses. For example, when the received portion of the bundle of lighthas a first color (e.g., in FIG. 1D, the received portion of the bundleof light has a red color, which indicates that lens 130-1 needs to bemoved toward a left side to align with eye 140-1), the first set of oneor more lenses is moved toward the left side.

In some embodiments, the method further includes continuing to monitorthe color of a light received by an eye and adjust a lateral position ofthe lens (or continuing to monitor the color of a light received by eacheye and adjust lateral positions of the first lens and the second lens)until the first lens is accurately positioned (or both the first lensand the second lens are accurately positioned). In some embodiments, anaccurate positioning of a lens is indicated by whether a particularlight (e.g., having a particular color, such as green, and/or having aparticular time-dependent intensity pattern, such as a pulsingfrequency, a duty cycle, and/or an interval) is delivered toward a pupilof an eye.

In accordance with some embodiments, a device includes a first lightsource device configured to transmit a first light in a first direction(e.g., light source device 122-1 in FIG. 1L is configured to emit light134) and a second light source device configured to transmit a secondlight in a second direction (e.g., light source device 122-2 in FIG. 1Lis configured to emit light 154). In some embodiments, the seconddirection is distinct from the first direction. The device also includesa first set of one or more lenses (e.g., lens 130) configured fordirecting, toward a first eye of a user (e.g., a left eye), the firstlight from the first light source device and the second light from thesecond light source device so that the first light intersects with thesecond light at a first location (e.g., in FIG. 1L, light 134 and light154 intersect with each other). One or more of the first light and thesecond light provide a cue for adjusting a location of the first set ofone or more lenses relative to the first eye of the user (e.g.,adjusting a position of the first eye relative to the first set of oneor more lenses or adjusting a position of one or more lenses of thefirst set of one or more lenses relative to the first eye). For example,as shown in FIG. 1L, the user can determine that eye 140 is not locatedat a position that corresponds to the design eye relief of device 100based on not receiving both light 134 and light 154 through pupil 150 ofeye 140.

In some embodiments, the first light has a first set of properties. Thesecond light has a second set of properties that is distinct from thefirst set of properties. Each of the first set of properties and thesecond set of properties is characterized by a color and/or atime-dependent intensity pattern. For example, the first light has afirst color and the second light has a second color that is distinctfrom the first color. In another example, the first light has a firsttime-dependent intensity pattern (e.g., a pulsing frequency, a dutycycle, and/or an interval) and the second light has a secondtime-dependent intensity pattern that is distinct from the firsttime-dependent intensity pattern (e.g., the second light has a pulsingfrequency that is distinct from a pulsing frequency of the first light).In some embodiments, the first light has a time-independent intensitypattern (e.g., the intensity of the first light does not change overtime), and the second light has a time-dependent intensity pattern(e.g., the intensity of the second light changes over time). In someembodiments, the first light has a time-dependent intensity pattern, andthe second light has a time-independent intensity pattern.

In some embodiments, the first light source device is configured totransmit a third light (e.g., light 158 in FIG. 1O) in a third directionthat is distinct from at least one of the first direction and the seconddirection. The second light source device is configured to transmit afourth light (e.g., light 160 in FIG. 1O) in a fourth direction that isdistinct from at least one of the first direction and the seconddirection. In some embodiments, the fourth direction is distinct fromthe third direction. The first set of one or more lenses is configuredfor directing, toward the first eye of the user, the third light fromthe first light source device and the fourth light from the second lightsource device so that the third light intersects with the fourth lightat a second location that is distinct from the first location (e.g., asshown in the inset of FIG. 1O, light 158 intersects with light 160 at alocation that is distinct from a location where light 134 intersectswith light 154).

In some embodiments, a path of the first light before passing throughthe first set of one or more lenses and a path of the first light afterpassing through the first set of one or more lenses define a firstplane. A path of the second light before passing through the first setof one or more lenses and a path of the second light after passingthrough the first set of one or more lenses define a second plane. Thesecond plane is substantially parallel to the first plane (e.g., theangle between the first plane and the second plane is 20 degrees orless). A path of the third light before passing through the first set ofone or more lenses and a path of the third light after passing throughthe first set of one or more lenses define a third plane. The thirdplane is substantially parallel to the first plane (e.g., the anglebetween the first plane and the third plane is 20 degrees or less). Forexample, in FIG. 1O, the plane defined by light 134 before and afterpassing through lens 130 is parallel to the plane defined by light 154before and after passing through lens 130 and the plane defined by light158 before and after passing through lens 130.

In some embodiments, a path of the first light before passing throughthe first set of one or more lenses and a path of the first light afterpassing through the first set of one or more lenses define a firstplane. A path of the second light before passing through the first setof one or more lenses and a path of the second light after passingthrough the first set of one or more lenses define a second plane. Thesecond plane is substantially parallel to the first plane (e.g., theangle between the first plane and the second plane is 20 degrees orless). A path of the third light before passing through the first set ofone or more lenses and a path of the third light after passing throughthe first set of one or more lenses define a third plane. The thirdplane is substantially perpendicular to the first plane (e.g., the anglebetween the first plane and the third plane is between 70 degrees and110 degrees).

In some embodiments, the first light source device is further configuredto transmit a fifth light (e.g., light 162 in FIG. 1O) in a fifthdirection that is distinct from the first direction and the thirddirection. The second light source device is further configured totransmit a sixth light (e.g., light 164 in FIG. 1O) in a sixth directionthat is distinct from the second direction and the fourth direction. Thefirst set of one or more lenses is further configured for directing thefifth light and the sixth light toward the first eye so that the fifthlight intersects with the sixth light at a third location that isdistinct from the first location and the second location (e.g., as shownin the inset of FIG. 1O, light 162 intersects with light 164 at alocation that is distinct from a location where light 134 intersectswith light 154 and a location where light 158 intersects with light160).

In some embodiments, the first light has a first set of properties. Thesecond light has a second set of properties that is distinct from thefirst set of properties. The third light has a third set of propertiesthat is distinct from the first set of properties and the second set ofproperties. The fourth light has a fourth set of properties that isdistinct from the first set of properties, the second set of properties,and the third set of properties. Each of the first set of properties,the second set of properties, the third set of properties, and thefourth set of properties is characterized by a color and/or atime-dependent intensity pattern. For example, the first light can bedistinguished from the second light, the third light, and the fourthlight based on the color and/or the time-dependent intensity pattern;the second light can be distinguished from the third light and thefourth light based on the color and/or the time-dependent intensitypattern; and the third light can be distinguished from the fourth lightbased on the color and/or the time-dependent intensity pattern.

In some embodiments, the first light source device includes a firstlight guide with one or more extraction features (e.g., light guide126-1 in FIG. 1J with extraction feature 128). The second light sourcedevice includes a second light guide with one or more extractionfeatures (e.g., another light guide that has a structure correspondingto light guide 126-1). The second light guide is distinct and separatefrom the first light guide. Each light guide of the first light guideand the second light guide is optically coupled with a respective lightemitting component (e.g., the first light guide is coupled with a greenLED, and the second light guide is coupled with a red LED).

In some embodiments, the device includes an electronic display (e.g.,light emission device array 110). The first light guide and the secondlight guide are located between the electronic display and the first setof one or more lenses (e.g., as shown in FIG. 1J, the first light guidecan be placed over light emission device array 110 so that the firstlight guide is located between light emission device array 110 and lens130).

In some embodiments, the device includes one or more input devicesconfigured for receiving a user input requesting an adjustment of adistance between the first eye and a lens of the first set of one ormore lenses (e.g., adjusting an eye relief). In some embodiments, eyepositioning device 184 is coupled with a mechanical positioning device,such as a linear motor, or a rotary motor coupled with a rail or a rackand pinion, and the device is configured to move eye positioning device184 in accordance with the user input requesting an adjustment of theeye relief (e.g., a user pressing a button initiate movement of eyepositioning device 184). In some embodiments, the one or more inputdevices comprise a rotating eyecup.

In some embodiments, the device includes a third light source devicethat is distinct from the first light source device and the second lightsource device and configured to transmit a seventh light in a seventhdirection. The device also includes a fourth light source device that isdistinct from the first light source device and the second light sourcedevice and configured to transmit an eighth light distinct from theseventh light in an eighth direction. In some embodiments, the eighthdirection is distinct from the seventh direction. The device furtherincludes a second set of one or more lenses configured for directing,toward a second eye of a user, the seventh light from the third lightsource device and the eighth light from the fourth light source deviceso that the seventh light intersects with the eighth light at a thirdlocation that is distinct from the first location and the secondlocation. For example, the first light source device and the secondlight source device are used for adjusting an eye relief for a left eye,and the third light source device and the fourth light source device areused for adjusting an eye relief for a right eye. The third locationcorresponds to a design eye relief for the right eye. In someembodiments, the first location and the third location correspond to asame eye relief (e.g., the device is configured for a same eye relieffor both left and right eyes).

In some embodiments, the third light source device is configured totransmit a ninth light in a ninth direction that is distinct from atleast one of the seventh direction and the eighth direction. The fourthlight source device is configured to transmit a tenth light in a tenthdirection that is distinct from at least one of the seventh directionand the eighth direction. In some embodiments, the tenth direction isdistinct from the ninth direction. The second set of one or more lensesis configured for directing toward the second eye of the user, the ninthlight from the third light source device and the tenth light from thefourth light source device so that the ninth light intersects with thetenth light at a fourth location that is distinct from the firstlocation, the second location, and the third location. For example, thefourth location does not correspond to a design eye relief for the righteye.

In some embodiments, a combination of the first light and the secondlight indicates that the first eye receiving both the first light andthe second light is at a predefined eye relief of the device (e.g., FIG.1M).

In some embodiments, the first light indicates that the first eyereceiving the first light is aligned with a center of the first set ofone or more lenses in one of a horizontal direction and a verticaldirection. For example, in FIG. 1N, light 134 indicates that eye 140 isaligned with lens 130 in a horizontal direction (e.g., a center of lens130 and a center of eye 140 are horizontally aligned, although they maybe offset vertically). The second light indicates that the first eyereceiving the second light is aligned with a center of the first set ofone or more lenses in the other of a horizontal direction or a verticaldirection. For example, in FIG. 1N, light 156 indicates that eye 140 isaligned with lens 130 in a vertical direction (e.g., a center of lens130 and a center of eye 140 are vertically aligned, although they may beoffset horizontally).

In some embodiments, the device includes one or more display screens(e.g., light emission device array 110) configured to project one ormore images through the first set of one or more lenses. In someembodiments, the device includes a single display screen for both leftand right eyes. In some embodiments, the device includes separatedisplay screens for the left and right eyes (e.g., a first displayscreen for the left eye and a second display screen that is distinct andseparate from the first display screen for the right eye).

In some embodiments, the device is a head-mounted display device (e.g.,FIG. 1R).

In some embodiments, the device includes an adjustable mount configuredto holding at least one lens of the first set of one or more lenses andmove a position of the at least one lens of the first set of one or morelenses. For example, the mount is slidably coupled with one or morerails. This allows adjusting a lateral position of the at least one lensof the first set of one or more lenses (e.g., FIGS. 1C-1E). In someembodiments, the device includes a first adjustable mount configured forholding at least one lens of the first set of one or more lenses andmoving a position of the at least one lens of the first set of one ormore lenses, and a second adjustable mount configured for holding atleast one lens of the second set of one or more lenses and moving aposition of the at least one lens of the second set of one or morelenses. In some embodiments, the first adjustable mount is mechanicallycoupled with the second adjustable mount (e.g., the at least one lens ofthe first set of one or more lenses and the at least one lens of thesecond set of one or more lenses move concurrently toward a nasal regionor toward respective temporal regions).

In some embodiments, the device includes a light source deviceconfigured to transmit, in conjunction with the first light sourcedevice transmitting the first light and the second light source devicetransmitting the second light, a reference light through the first setof one or more lenses (e.g., pixel 124 emits reference light 138).

In accordance with some embodiments, a method includes transmitting,from a first light source device, a first light in a first direction(e.g., light 134 from light source device 122-1 shown in FIG. 1L);transmitting, from a second light source device, a second light that isdistinct from the first light in a second direction (e.g., light 154from light source device 122-2 shown in FIG. 1L). In some embodiments,the second direction is distinct from the first direction. The methodalso includes transmitting the first light and the second light througha first set of one or more lenses and directing the first light and thesecond light toward a first eye of a user (e.g., a left eye of theuser). In some embodiments, the first light and the second light aretransmitted concurrently. However, the first light and the second lightneed not be transmitted concurrently. For example, the first light andthe second light are transmitted sequentially. In another example, thefirst light and the second light are transmitted alternatingly so thatthey are not transmitted concurrently.

In accordance with some embodiments, a method includes receiving aportion of a light beam that includes a first light from a first lightsource device (e.g., light 134 from light source device 122-1 as shownin FIG. 1L) and a second light that is distinct from the first lightfrom a second light source device (e.g., light 154 from light sourcedevice 122-2 as shown in FIG. 1L). The first light and the second lighthave been transmitted through a first set of one or more lenses. Aftertransmitting through the first set of one or more lenses, the firstlight is configured to intersect with the second light. The method alsoincludes, in accordance with a determination that the received portionof the light beam does not include both the first light and the secondlight, adjusting a distance between an eye and a lens of the first setof one or more lenses (e.g., adjusting an eye relief). For example, wheneye 140 does not receive, through pupil 150, both light 134 and light154 as shown in FIG. 1L, the user can determine that eye 140 is notlocated at a position that corresponds to a design eye relief, andinitiate adjusting the distance between eye 140 and lens 130 by rotatingan eyecup, sliding eye positioning device 184, activating an actuator,such as a motor, etc.

In some embodiments, the method includes, in accordance with adetermination that the received portion of the light beam includes boththe first light and the second light, ceasing to adjust the distancebetween the eye and the lens of the first set of one or more lenses(e.g., when eye 140 receives, through pupil 150, both light 134 andlight 154 as shown in FIG. 1M, the user can determine that eye 140 islocated at a position that corresponds to a design eye relief, and stopsadjusting the distance between eye 140 and lens 130).

Although some of various drawings illustrate a number of logical stagesin a particular order, stages which are not order dependent may bereordered and other stages may be combined or broken out. While somereordering or other groupings are specifically mentioned, others will beapparent to those of ordinary skill in the art, so the ordering andgroupings presented herein are not an exhaustive list of alternatives.Moreover, it should be recognized that the stages could be implementedin hardware, firmware, software or any combination thereof.

The foregoing description, for purpose of explanation, has beendescribed with reference to specific embodiments. However, theillustrative discussions above are not intended to be exhaustive or tolimit the scope of the claims to the precise forms disclosed. Manymodifications and variations are possible in view of the aboveteachings.

For example, in accordance with some embodiments, a device includes afirst light source device configured to transmit a first light in afirst direction (e.g., and not in a second direction that is distinctfrom the first direction). In some embodiments, the first light sourcedevice includes barrier 146 with an opening (e.g., a pinhole or a slit)and light emitting component 142-2, but not light emitting components142-1 and 142-3 shown in FIG. 1G. In some embodiments, the first lightsource device includes lens 144 (e.g., a cylinder lens) and lightemitting component 142-2, but not light emitting components 142-1 and142-3 shown in FIG. 1F. The device also includes a first set of one ormore lenses configured for directing the first light toward a first eyeof a user. The first light is spatially restricted (e.g., a beam of thefirst light directed toward the first eye of the user has a width or adiameter less than 5 mm, 4 mm, 3 mm, 2 mm, or 1 mm). The first lightprovides a cue for adjusting a location of the first set of one or morelenses. In some embodiments, the first light is transmitted through alateral center of the first set of one or more lenses. Thus, when a usersees the first light with the first eye, this indicates that the firstset of one or more lenses is aligned with the first eye. When the userdoes not see the first light with the first eye, this indicates that thefirst set of one or more lenses is not aligned with the first eye.

In accordance with some embodiments, a method includes transmitting afirst light in a first direction, and transmitting the first lightthrough a first set of one or more lenses and directing the first lighttoward a first eye of a user. The first light is spatially restricted.The first light provides a cue for adjusting a location of the first setof one or more lenses.

In accordance with some embodiments, a method includes receiving atleast a portion of a bundle of a first light that is spatiallyrestricted. The method also includes, in accordance with a determinationthat the at least a portion of a bundle of the first light is received,moving the first set of one or more lenses (e.g., based on an intensityof the received portion of the bundle of the first light so that acenter of the bundle of the first light is received by a first eye of auser). Alternatively, the method includes, in accordance with adetermination that no portion of the bundle of the first light isreceived, moving the first set of one or more lenses (because the firstset of one or more lenses is not aligned with the first eye of theuser).

The embodiments described herein were chosen in order to best explainthe principles underlying the claims and their practical applications,to thereby enable others skilled in the art to best use the embodimentswith various modifications as are suited to the particular usescontemplated.

What is claimed is:
 1. A device, comprising: a first light source deviceconfigured to provide a first light in a first direction and a secondlight in a second direction that is distinct from the first direction; asecond light source device configured to provide a third light in athird direction that is distinct from the first direction and a fourthlight in a fourth direction that is distinct from the second direction;and a first set of one or more lenses configured for directing, toward afirst eye of a user, the first light and the second light from the firstlight source device and the third light and the fourth light from thesecond light source device so that the first light intersects with thethird light at a first location at a first distance from the first setof one or more lenses and the second light intersects with the fourthlight at a second location at a second distance, distinct from the firstdistance, from the first set of one or more lenses, wherein: the firstlight, the second light, the third light, and the fourth light aredistinguishable from one another based on at least one of: a color and atime-dependent intensity pattern; the first set of one or more lensesdefines a first optical axis; the first light source device includes atleast two light sources and an optical element optically coupled with atleast the two light sources for steering the first light in the firstdirection and steering the second light in the second direction; and thefirst light source device, including at least the two light sources andthe optical element, is positioned away from the first optical axis. 2.The device of claim 1, wherein: the first light has a first set ofproperties; the third light has a second set of properties that isdistinct from the first set of properties; and each of the first set ofproperties and the second set of properties is characterized by a colorand/or a time-dependent intensity pattern.
 3. The device of claim 1,wherein: a path of the first light before passing through the first setof one or more lenses and a path of the first light after passingthrough the first set of one or more lenses define a first plane; a pathof the third light before passing through the first set of one or morelenses and a path of the third light after passing through the first setof one or more lenses define a second plane; the second plane issubstantially parallel to the first plane; a path of the second lightbefore passing through the first set of one or more lenses and a path ofthe second light after passing through the first set of one or morelenses define a third plane; and the third plane is substantiallyparallel or substantially perpendicular to the first plane.
 4. Thedevice of claim 1, wherein: the first light source device is furtherconfigured to provide a fifth light in a fifth direction that isdistinct from the first direction and the second direction; the secondlight source device is further configured to provide a sixth light in asixth direction that is distinct from the third direction and the fourthdirection; and the first set of one or more lenses is further configuredfor directing the fifth light and the sixth light toward the first eyeso that the fifth light intersects with the sixth light at a thirdlocation that is distinct from the first location and the secondlocation.
 5. The device of claim 1, further comprising: an eyepositioning device configured for adjusting a distance between the firsteye and a lens of the first set of one or more lenses.
 6. The device ofclaim 1, wherein: a combination of the first light and the third lightindicates that the first eye receiving both the first light and thethird light is at a predefined eye relief of the device.
 7. The deviceof claim 1, wherein: the first light indicates that the first eyereceiving the first light is aligned with a center of the first set ofone or more lenses in one of a horizontal direction and a verticaldirection; and the third light indicates that the first eye receivingthe third light is aligned with a center of the first set of one or morelenses in the other of a horizontal direction or a vertical direction.8. The device of claim 1, further comprising: a light source deviceconfigured to transmit, in conjunction with the first light sourcedevice providing the first light and the second light source deviceproviding the third light, a reference light through the first set ofone or more lenses.
 9. The device of claim 1, wherein the opticalelement is further configured to: steer the first light in the firstdirection without steering the first light in the second direction; andsteer the second light in the second direction without steering thesecond light in the first direction.
 10. The device of claim 1, whereinthe optical element is selected from a group consisting of: a lens, abarrier with a pinhole, an optical grating, a set of dichroic mirrors,and a light guide.
 11. The device of claim 1, wherein: the second lightsource device is distinct and separate from the first light sourcedevice and includes at least two light sources and an optical elementoptically coupled with at least the two light sources of the secondlight source device for steering light from at least the two lightsources of the second light source device; and the second light sourcedevice is positioned away from the first optical axis so that the firstoptical axis does not intersect at least the two light sources and theoptical element of the second light source device.
 12. The device ofclaim 1, wherein: the second light source device includes a light guidewith one or more extraction features.
 13. The device of claim 12,further comprising: an electronic display, wherein the light guide islocated between the electronic display and the first set of one or morelenses.
 14. The device of claim 1, further comprising: a third lightsource device that is distinct from the first light source device andthe second light source device and configured to provide a seventh lightin a seventh direction; a fourth light source device that is distinctfrom the first light source device and the second light source deviceand configured to provide an eighth light distinct from the seventhlight in an eighth direction; and a second set of one or more lensesconfigured for directing, toward a second eye of a user, the seventhlight from the third light source device and the eighth light from thefourth light source device so that the seventh light intersects with theeighth light at a third location that is distinct from the firstlocation and the second location.
 15. The device of claim 14, wherein:the third light source device is configured to provide a ninth light ina ninth direction that is distinct from at least one of the seventhdirection and the eighth direction; the fourth light source device isconfigured to provide a tenth light in a tenth direction that isdistinct from at least one of the seventh direction and the eighthdirection; and the second set of one or more lenses is configured fordirecting toward the second eye of the user, the ninth light from thethird light source device and the tenth light from the fourth lightsource device so that the ninth light intersects with the tenth light ata fourth location that is distinct from the first location, the secondlocation, and the third location.
 16. The device of claim 1, wherein thedevice is a head-mounted display device.
 17. The device of claim 16,further comprising: an adjustable mount configured to holding at leastone lens of the first set of one or more lenses and move a position ofthe at least one lens of the first set of one or more lenses.
 18. Amethod, comprising: providing, from the first light source device of thedevice of claim 1, the first light in the first direction and the secondlight in the second direction; providing, from the second light sourcedevice, the third light that is distinct from the first light in thethird direction and the fourth light in the fourth direction;transmitting the first light, the second light, the third light, and thefourth light through the first set of one or more lenses and directingthe first light, the second light, the third light, and the fourth lighttoward the first eye of the user; and steering, with the opticalelement, the first light in the first direction and the second light inthe second direction.
 19. The method of claim 18, comprising: receivinga portion of a light beam that includes the first light from the firstlight source device and the third light that is distinct from the firstlight from the second light source device, wherein: the first light andthe second light have been transmitted through the first set of one ormore lenses; and after transmitting through the first set of one or morelenses, the first light is configured to intersect with the secondlight; and in accordance with a determination that the received portionof the light beam does not include both the first light and the thirdlight, adjusting a distance between the first eye of the user and a lensof the first set of one or more lenses.
 20. A device, comprising: afirst light source device configured to provide a first light in a firstdirection and a second light in a second direction that is distinct fromthe first direction; a second light source device configured to providea third light in a third direction that is distinct from the firstdirection and a fourth light in a fourth direction that is distinct fromthe second direction; and a first set of one or more lenses configuredfor directing, toward a first eye of a user, the first light and thesecond light from the first light source device and the third light andthe fourth light from the second light source device so that the firstlight intersects with the third light at a first location at a firstdistance from the first set of one or more lenses and the second lightintersects with the fourth light at a second location at a seconddistance, distinct from the first distance, from the first set of one ormore lenses, wherein: the first light, the second light, the thirdlight, and the fourth light are distinguishable from one another basedon at least one of: a color and a time-dependent intensity pattern; andthe first light source device is configured to provide the first lightin the first direction and the second light in the second directionwithout providing the first light in the second direction and withoutproviding the second light in the first direction.